Water-tube boiler



1,576,310 A. COTTON W'ATEH TUBE BOILER Filed March 20, 1922 s sheets-sheet 1 Fig.1

March 9 1926.

INVENTORZ ALFRED CoT'roN :KTTU Rhfilfi.

March 9 1926. 1,576,310

A.COTTON WATER TUBE BOILER Filed March 20, 1922 3 Sheets-Sheet 2 Fiq' 2 2 6 nu 3 2f 4 INVENTORI ALFRED COTTON ATTORNEYS.

A. COTTON WATER TUBE BoiLER March 1926.

l 05 2 I h G G ra F d WWW INVENTOB';

' ALFRED COTTON BY 7 g E -ATTORNEYS.

Patented Mar. 9, 1926.

l,576,3ll3

UNITED STATES PATENT QFFIQE.

ALFRED COTTON, OF ST. LOUIS, MIEISOUBI, ASSIGNDR TO HEINE BOILER ClOMPANY, OF

ST. LOUIS, MISSOURI, A CORPORATION OF MISSOURI.

we'rna rnnn BOILER.

Application filed March 20, 1822. Serial No. 545,134.

To (ZZZ whom it may concern:

Be it known that I, ALFRED COTTON, a citizen of the United States, residing at St. Louis, Missouri, have invented a certain new and useful Improvement in Water- Tube Boilers, of which the following is a full, clear, and exact description, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to water tube boilers of the type in which the water tubes are arranged in a horizontally-inclined position between front and rear header structures to which the ends of said tubes are connected The water tube boilers of this general type that are now in use comprise a main tube bank of relatively long tubes that is divided into a plurality of gas passes either by transverselydisposedbaffles arranged in such a way as to cause the gases to flow transversely across the tubes, or longitudinallydisposed baffles arranged in such a way as to cause the gases to flow lengthwise of the tubes. The battles of water tube boilers of the general type referred to are difficult and expensive to construct and in most instances it is virtually impossible to inspect them. They become defective and leaky in service, but there is no way of ascertaining this except by suspicion engendered by reduced boiler eliiciency. Owing to the fact that such baffles are so inaccessible that they can only be repaired when the boiler is not'in operation, the waste, due to defective baffles, is frequently allowed to continue for long periods, as it is often almost impossible,or at least highly undesirable, to shut the boiler down long enough to enable the baffles to be repaired. Gross battles are particularly expensive to construct, and due to the fact that they are arranged transversely of the tubes, they are very liable to become damaged when renewing the water tubes of the boiler.

The main object of my invention is to pro vide a water tube boiler of the type thatcomprises horizontally-inclined tubes which is of such construction that a long, tortuous gas passageway of diminishing cross-sectional area is obtained without baffles. or without inaccessible bafl'les that catiilot be inspected or repai red easily, ninety prodiie 'ing a l'iighly efficient boiler that is free from bank of uniform width throughout its entire height but of diminishing cross-sectional area, through which the gases make a single pass, composed of horizontal or horizontally; inclined water tubes of gradually diminish-j inglength, a header structure arranged at one end of the tubes constituting said'banlc and an inclined header structure arranged at the opposite ends of saidtubes and setat such an angle with relation to the header structure fi st referred to asto form a gas passageway of uniform width throughout its entire length or height, but of gradually din'iinishing depth from its lower towards its upper end. V I

Figure l of the 'drawings is a Vertical longitudinal sectional view of a water tube boiler constr cted in accordance with my invention. i

' Figure l is a longitudinal sectional View, illustrating a portion of a boiler of the construction shownin Figure'l equippedwith a superheater. I r I Figures 2 and 3 are vertical longitudinal sectional views, illustrating other forms of my invention; and

Figure 3 is aview, illustrating another form of inclined front header.

Referring to Figure 1 of the drawings, which illustrates the basic idea which my improved boiler embodies, A designates the combustion chamber of the boiler and B designates the main tube bank which is composed of horizontally-inclined Water tubes-1, a rear header structure composed preferably of vertically disposed, sectional headers to which his rear ends of the tubes 1 are connected and a front header structure composed preferably of inclined sectional headers 3 of stepped form or zigzag shape to which the front ends of the tubes 1 are connected. Above the main tube bank B is a shallow top bank C composed of relatively long water tubes 4 arranged parallel to the tubes of the main bank B and connected at their front and rear ends to headers 5 and 6 which are connected with the front and rear header structures of the main bank B by means of water circulators 7 and 8, respectively. A transverse steamand-water drum D is connected by means of water circulators9 with the front header structure 5 of the top bank C, and said drum is connected'by means of steam circulators 10 with the rear header structure 6 of the top bank C. The substantially triangular-shaped space between the front wall of the setting of the boiler and theinclined front header structure 3 of the main bank G constitutes a dust and ashcollection chamber E that is large enough to allow a large accumulation of dust and fly ash and to which access may be had through a door opening 11 in one of the 'side walls of the boiler setting. If desired, the front wall of the setting may be provided with a door or doors 12 so as to permit the dust and ash to be removed from the chamber E by devices inserted between the water circulators 7 that connect the front header structures of. the two tube banks of the boiler. Preferably, plates 13 provided with handles 13 are mounted oirthe inclined front headers-3 of the main tube bank B so as to prevent dust and ash from collecting on the hand hole plates: (not shown) of said front headers, the plates 13 being narrow enough to permit them to be removed easily from the dust'collection chamber E. A shield 14 that is arranged on the upper side of the top bank C extends forwardly from the rear header structure '6 of said bank to an uptake 15 that leads to a chimney or stack 16 and the steam circulators 1O that connect the steam-and-water drum D with the rear header structure 6 of the top bank G are protected by the top wall 17 of the boiler setting.

lVhen the boiler is in operationthe gases rising from the fire flow upwardly across the tubes of the main bank B and then longitudinally of the shallow top} bank G to the uptake 15 at the front end of said top bank, Owing to the fact that the boiler comprises a shallow top bank C of long tubes that is arranged above themain tube bank 13, the heating surface of the boiler is equal to the heating surface of a conventio'nal, horizontally-inclined tube. boiler having a single tube bank of long tubes that is divided into a number of passes by-trans versely-disposed cross baffles. As the gases bank Band the top bank 0, as shown in Figure 1. y

In Figure 2 of the drawings I have shown another form of my invention consisting of a boiler having the desirable features and clntracteristics of the boiler shown in Figure 1 and equipped with a bank G of long tubes exposed to the radiant heat of the combustion chamber A. Host of the elements of the boiler shown in Figure 2 are of the same construction and arrangement as the elements of the boiler shown in Figure 1, and accordingly have been designated by corresponding reference characters. The main difference consists in the addition of the radiant heat bank G of long water tubes arranged between the combustion chamber A and the main tube bank B and the addition of a superheater H that is arranged directly above the radiant heat bank G in the space between said bank and the main tube bank 13. By arranging the superheaterin this position it will be exposed to higher temperature gases than the superheater' shown in Figure 1. Consequently, it may be made smaller because the heating surface is more effective. In the boiler shown in Figure 2 the inclined front headers 3 of the main bank are provided at their lower ends with forwardly-projecting extensions 3 that overhang the front end portions of the tubes of the radiant heatbank G, and the spaces between said extensions are packed with refractory material so as to form a wall that prevents the gases from short-'circuiting into the dust collection chamber E. it is preferable but not absolutely necessary to arrange a shield at the upper side of'the front end portion of the radiant heat bank G, so as to protect the lower end portions of the inclined front headers 3 from the hot gases, the shield of the boiler herein illustrated being formed by tiles 18 arranged over the front end portions of the topmcst tubes of the radiant heat bank and a transversely-disposed member 18 at the front end of the super-heater chamber which projects upwardly high enough to protect the forwardly projecting extensions 3 at the lower ends of the inclined front headers 3 of the main tube bank. Another slight difference between the boiler shown in Figure 2 and the boiler shown in Figure 1. is that theshield 1. L?

arranged above the top bank C is so con structed that the flow of the gases through said top bank is partly longitudinally of said bank and partly transversely of said bank. Fewer tubes are used in the top bank of the boiler shown in Figure 2, but there is no serious throttling 0t thcgases in traveling through said top bank, owing to the fact that openings 19 and 20 are provided at opposite ends of th shield 14 so as to permit a shunt flow of some of the gases into adu'st collect-ion chamber I above the top'bank, as indicated by the arrows in Figure 4'. lVhen the boiler shown in Figure 2 is in operation part of the gases that escape from the upper end of the main bank l3 flew longitudinally of tne top bank G into the uptake 15 and the remainder of said gases flow transversely across the rear end portion of the tubes of the top bank G into the chamber I and then downwardly through the opening 20 among the tubes of the top bank C, finally escaping upwardly through the uptake 15. Accordingly, in the boiler shown in Figure 2 the flow of the gases relative to the top bank C is partly longitudinally of said bank and partly transversely of said bank, and gas pockets are avoided, while the resistance to gas flow is small with low draft loss. The

avoidance of gas pockets increases the effective heating surface of the boiler and increases its ei'iiciency over the conventional,

horizontally-inclined tube boilers of the kind now in commercial use. Any deposit of dust on the shield 145* of the boiler shown in Figure 2 is not objectionable, since such dust does not lie on the heating surface of the boiler. Even if the removal ct such dust is neglected, it will eventually be carried down into the dust collection chamber E through the opening 20 at the lower end or front end of the downwardly-inclined shield 14L ar anged above the top bank.

While I prefer to construct the top tube bankot my improved boiler in. the manner illustrated in Figure 2, it is not essential that the top tube bank be constructed in the manner illustrated in Figure 2 or in Figure 1, for if desired, the boiler may be provided with a rather high top tube bank G, as shown in Figure 3, equipped with cross bafties 2-1 and arranged in such a way as to cause the gases to make a number of transverse passes in traveling from the main tube bank B to the uptake 15. Due to the fact that the top bank 0' of the boiler illustrated in Figure 3 is shallow, as compared to the main tube bank 13, being a maximum of about eight tubes high or deep, the cross battles 21 and 22 01. said top bank are accessible either from above or below said can be easily installer]. or repaired, as no porform that the velocity of the gases traveling through same will be kept constant. In a boiler of theconstruction illustrated in Figures 1, 2 and 3, the gases flowing through the main tube bank will be maintained at a substantially constant velocity, due to the fact that the gas passage in the main tube bank is formed by the two side walls of the boilersetting, the rear headers 2 and the front headers 3 which are set at such an angle with relation to the rear headers as to form a gas passage of diminishing area from its lower towards its upper end. If, however, it is desired to hold the velocity of the gases within closer limits, the main tube bank can be provided with front headers or horizontally-disposed soot blowers. With such a boiler it is not necessary to carry a large stock of tubes for renewals, for the tubes which fall most frequently are those nearest the fire, and-these tubes are long tubes.

If long tubes only are carried in stock, they can be out down for the renewal oi? short tubes, and as short tubes fail very seldom, the loss due to cutting is outweighed by the less amount of stock it is necessary to carry on hand. Y

Havlng thus described my invention, what I claim and desire to secure by Letters Pat- 'ent is: V y v 1. A water tube boiler provided with a main tube bank composed of tubes that diminish in length in the direction inwhich the gases flow through the boiler, an inclined header structure arranged bet-ween the said bank and one wall of the boiler settingso as to fol-ma dust collection chamber between said wall and header structure, and a top tube bank arranged so that portion. of same extends beyond said header structure and over'isaid dust collection chamber.

2. A water tube boiler having a main tube bank provided at one end with an inclined header structure that is soaced away from one wall of the boiler sett ng so as to -form a dust collection chamber between said wall and header structure, and a top tube bank arranged so that one portion of same is positioned over said main tube bank and a different portion of same is positioned over said dust collection chamber.

' as to form a dust collection chamber between said front wall andsaid front header structure, and a top bank of relatively long tubes arranged so that a portion of same extends forwardly over said chamber.

4. A water tube boiler provided with a.

main bank of horizontally-inclined water tubes arranged so that the gases from the fire will flow-transversely across same, angularly-disposed header structures combined with said tubes in such a way as to form a,

gas passageway of gradually diminishing area from its lower towards its upper end, a top tube bank composed of relatively long water tubes combined with header structures that are connected by circulators with the header structures of the main bank, and

steam-and-water drum connected by water circulators and steam circulators with the header structures of said top bank.

5. A water tube boiler having a main tube bank, comprising horizontally-inclined water tubes arranged above the combustion chamber, an inclined header structure at one end of said bank spaced away from a wall of the boiler setting so as to form a dust collection chamber between said wall and header structure, 'a gas uptake at the upper end of the boiler arranged above said dust collection chamber, and a top tube bank arranged between said gas uptake and said main tube bank and provided with a portion that overhangs said dust collection chamber.

V (i. A water tube boiler having a main tube bank, comprising horizontally-inclined water tubes arranged above the'combustion chamber, an inclined header structure at one end of said bank spaced away from a wall of the boiler setting so as to form a dust collection chamber between said .wall and header structure, a gas uptake at the upper end of the boiler arranged above said dust collection chamber, a top tube bank arranged between said gas uptake and said main tube bank and provided with a portion that extends over said dust collection chamber, means for facilitating the removal of dust from said chamber, and means for preventing dust from accumulating on-the inclined header structure of said main bank.

7. A water tube boiler, comprising a main bank composed of horizontally-inclined water tubes and a-ngularly-disposed header structures combined with said tubes, a top bank composed of relatively long water tubes arranged above said main bank, a radiant heat bank arranged between said main bank and the combustion chamber of the boiler, and means for causing the gases to flow partly longitudinally of and partly transversely of said top bank.

8. A water tube boiler, comprising a main bank composed of horiZontally-inclined water tubes and angularly-disposed header structures combined with saidtubes, a top bank composed of relatively long water tubes arranged above said main bank, a radiant heat bank arranged between said main bank and the combustion chamber of the boiler, an uptake leading from one end of said top bank, and means combined with said top bank for causing part of the gases that escape from the main bank to flow longitudinally of the top bank and the re mainder of said gases to make a plurality of transverse passes in traveling through said I top bank. 7

9. A water tube boiler provided with a main bank composed of horizontallyinclined water tubes and angularly-disposed header structures combined in such a way as to form a gas passageway of gradually diminishing cross-sectional area from its low'er'towards its upper end, a top bank composed of tubes of greater length than most of the tubes of said main bank, a gas uptake leadingfrom one end of said top bank, and a shield arranged above the por tion of the top bank that is in proximity to said main bank and provided at its ends with openings that permit some of the gases escaping from the main bank to flow transversely of the tubes of the top bank in traveling to said uptake.

10. .A water tube boiler provided with a main bank composed of horizontally-inclined water tubes and angularly-disposed header structures combined in such a way as to form a gas passageway of gradually diminishing cross-sectional area from its lower towards its upper end, a top bank composed of tubes of greater length than most of the tubes of said main bank, a gas uptake leading from one end of said top bank, a shield arranged above the portion of the top bank that is in proximity to said main bank'and provided at its ends with openings that permit some of the gases escaping from the main bank to flow transversely of the tubes of the top bank in traveling to said uptake, and a radiant heat bank arranged between said main bank and the combustion chamber.

11. A. water tube boiler, comprising a main tube bank composed of tubes of gradually diminishing length from the-lower tostituting the main bank, and means inter- Wards the upper end of the bank, angularlyposed between said radiant heat bank and 10 disposed header structures arranged at the the lower end portion of one of the header opposite ends of said tubes, a top bank comstrurtures of the main bank for protecting posed of relatively long tubes, a radiant heat the lower portion of said header structure bank arranged between the combustion from the fire gases.

chamber and said main bank and composed of tubes of greater length than those eon- ALFRED COTTON. 

